Various photochemical advanced oxidation processes that have been sugg
ested for the oxidation of organic compounds in water and waste water
are described. In the first part pollutant degradation by ultraviolet
photolysis is presented. Further, the various photochemical processes
such as H2O2/UV, O-3/W, O-3/H2O2/UV, TiO2/UV, and photo-Fenton reactio
n are discussed. Finally, the sonochemical degradation of organic comp
ounds is included. The utilization of photochemical methods for water
purification is illustrated by examples concerning the degradation of
organic pollutants in water. Some probable reaction mechanisms are als
o given.